The general thoughts that went
into the overall plan in designing this room was to accommodate not only audio
but video.The acoustic plan was to
eliminate as many parallel surfaces as possible.The side walls are skewed out by 2” from
front to back to help reduce slap echos.Both the front and the back of the room incorporate a curve design that
would help scatter sound.I replicated the
ceiling design from a concert hall in Osaka, Japan.The ceiling to floor dimension at the front
of the room, 11.5 feet, expanded in five different planes to 17.5 feet at the
rear of the room.
The walls of the room were built
with 12” cinderblock.Durawall wire
reinforcement was incorporated in between each vertical course.A 1” rebar was inserted into every other vertical
cavity and then the cavities were filled solid with 3500 PSI pea gravel concrete.The walls were framed with 2 x 6studs on 12” centers.Purlins were inserted and spaced 48” apart in
each vertical cavity.
A dedicated 200 Amp service
supplied all the power requirement for lighting, HVAC, wall outlets, and
dedicated 220 volt outlets for all of the equipment.Fiberglass insulation was then installed in
the walls before ¾” plywood sheeting was glued and screwed over all of the
studs.Two layers of 5/8” fire code
sheetrock were then glued, with Durabond 90, and screwed to the ¾” plywood.
The ceiling was built using trusses on 16” centers spanning from
the front to the rear of the room. The trusses were designed with a space varying
from 10” to 24” in between the top and bottom cords. This space
was designed to accommodate additional insulation, lighting, and HVAC.The ceiling was finished using ¾” tongue and groove
western ridge cedar.This was glued and
stapled to the trusses.The floor was
poured using 3500 PSI concrete to a thickness of 8”.
Acoustic testing was then done by
a Richmond company, “Acoustics First”.ETF measurements were taken and sound panels
were then designed according to a patented algorithm.The panels were then built by Owens Corning
according to prescribed specification.
The finished trim in the room was done in 18th
century motif that incorporated a combination of hardwood raised panels and
appropriately painted trim.Hardwood
tongue and groove flooring was applied over a ¾” plywood substrate glued and
fastened to the concrete floor.
The main electronics in this system
mostly come from Krell.I have always
been a fan of their electronic design and robust construction.Their reputation for quality electronics made
my choices easy.The choice of
additional electronics pretty much fell in line and the choices can be viewed in
From the time the room was
finished until present, I have had four different loudspeaker systems starting
with a pair of Electro Voice Patricians I built 50 years ago.Being a DIY guy, I always built loudspeaker
systems that were tailored to my personal sonic choices rather than having to
settle for speaker systems designed by others for mass appeal.
Being an audiophile, I am always
searching for better sound and the equipment it takes to experience better
sonic satisfaction.The only limitation
is my lovely wife Sue.
Direct drive turntable with numerical tach display
Ampex ATR 102 - Aria
Ampex ATR 102 reel to reel tape machine, record and play. 1/4 inch 2 track and 1/2 inch 2 track.
Krell KBX electronic crossovers, five
Electronic crossovers for three front and four surround channels and sub control via the 707 at 60 hz.
Krell Krell EVO 707 processor, one Krell EVO 202 preamp, two
front end controllers
Krell FPB 600, three- FPB 300, four, EVO 403, one
Class A power amps
Minus K 200 BM 4
200 LB capacity vibration abatement platform
Three channel input phono pre
This is a diy, home brew table. Platter is a Sota vacuum table fitted with an 80 lb. lead platter. Three VPI HRX motor drives on a custom built FRP epoxy plinth with 220 lbs of epoxy lead internal ballast. total weight 530 lbs.
Minus K 750 BM
custom built 750 lb. capacity vibration platform
Kuzma Air Line- two
An air bearing straight line tonearm.
Kuzma Four point - 9
nine inch tone arm
low out put moving coil cartridge
Koetsu Platinum Signature Jade
Low output moving coil cartridge
Dynavector XV 1 S
Low output moving coil cartridge
Three channel phono pre
Crane Song Trakker
Peak limiter mastering amplifier
Crane Song STC 8
two channel peak limiting mastering amplifier
OPPO UDP 205
Blu Ray DVD, CD player
Bricasti M - 1
two channel DAC
Crest Audio Pro 9200- four amplifiers
solid state, class H, 6500 watt stereo amplifiers, four units to drive sub woofers
APC SMX 1000, four units
1000 watt smart UPS battery backups for all front end equipment
Synology DS 1817
20 terabyte hard drive storage for CD material
Tivo Roamio- Pro
TV recording and storage device
Sony PLV 1100ES
3d - 4K video projector
Stewart Film Screen Electrascreen 135
135 inch, perforated projection screen
DIY line source loudspeaker, three for front
9.5 ft tall, three way speaker. Twenty four-7 inch Scan Speak Revelator mid bass drivers, four BG RD 50 planar mids, four BG RD 50 planar mids, forty Panasonic EAS 10TH 400A leaf tweeters
DIY 7.5 ft line source surround towers, four
Six Scan Speak 8 inch Revelator bass drivers, six Scan Speak 3 1/2inch Revelator mid drivers, six Scan Speak Revelator silk dome tweeters.
Krell 15 inch metal cone woofers,
Woofers sourced from Krell as used in their Master Reference Subwoofer. Eight drivers per side, each in their separate sealed enclosures with cone xmax of 2 inches.
Yes, I do have a wive of 25 years. Before I asked her to marry me she worked for my company for 10 years and was ALWAYS ON TIME and was also the best worker I've ever had. I was very particular about my products and always gave my customers more than they paid for. Sue know the type of person I was so it came as no surprise that I would be into my hobby to the same degree I was into my company. I need to also mention that at one time Sue said she thought a Bose was good enough<*>.
In regards to the Cranesongs; The planar mids from BG haven't been made for around 13 years and the Panasonic Leaf tweeters for about 20 years. I'm driving four BG RD 50 planners wired two in series and two pairs in parallel with one half of a Krell FPB 600 and 40 of the tweeters with one third of a Krell EVO 403 400 watt three channel amp. In the past I've incinerated four tweeters and four planar mids. I have a few spares for each but I can't count on nev having an accident by turning the level up too high.
I also have a good deal of pro recording gear and therefore decided to put peak limiters in the feed to the Krells. I wanted the best of the best and the Cranesong STC 8M are mastering grade limiter compressors. I won't be using them as compressors, just peak limiters. I first decided to limit the entire three front channels so I bought one stereo and one mono unit. After some thought I knew there was no need to peak limit the twenty four Scan Speak mid bass drivers. I also realized different degrees of limiting were best for the mids and tweeters. I will be getting two more STC 8M two channel units from Cranesong within a week so I can selective limit the three channels of the mids and tweeters independently with six channels of limiters.
The need for the limiting is really only when we put on a DVD where the bombs, gunfire and explosions will take their tolls on the drivers.
Regarding a visit, please email anytime you might be in the area and we can set up an audition.
To show off the system I use Laura Branigan, platinum collection. Gloria and The power of love are spectacular along with Fleetwood Mac's Go your own way . For classical both Bethoven's Moonlite Sonata and Mahler's Resurrection are startling. When the CDs and LPs are done I put a few master tapes from The Tape Project on the Ampex ATR and it puts everything else to shame.
Thanks for your comments and please do call when you're in the area.
The screen is a Stewart Electrascreen 135. It is also a perforated unit that descends with the touch of a remote control and is adjusted to the proper position when I first installed it.
On another note, the center channel and the four rear and since surrounds are only used for home theater. The Krell 707 processor has a feature that enables all the speakers to be on simultaneously but I have never chosen to do so.
When I was ready to purchase my projector lasers were not quite on the horizon yet. As it turn out, Sony came out with their first laser projector one year after my purchase. The picture quality we experience is just fabulous so I never lusted for a newer model.
Ken, absolutely superb! So many years in design and construction, I know it must be very satisfying to have this marvelous listening room finally finished! At least until the next project comes into your mind! :-) You've done exceptionally fine work on all of this.
Although the system isn't in a funeral home the room size could be used as a reception and showing space in one.
Over the years I've heard many great systems in many different rooms. One of the thoughts I sometimes had after listening for a while was,"Wow, the gear and speakers sound great but the room seems a bit small and probably limits the sound the loudspeakers are capable of."
Even display rooms in audio salons, for the most part, limit what the systems can do unless the rooms were purpose built for audio reproduction by specific speaker systems. A local audio shop even removes all speakers except the pair being demoed as he feels cones not powered in a room deter the performance of those being run, how about that. I realize it's not always possible for an audiophile to expand a room to fit their system choices. Many of us graduate to larger systems because we can afford it without considerations of the room the speakers will occupy.
I was fortunate in that I had a pair of Electro Voice Patricians I had built before I moved to Virginia. I had them in a 12 x 20 ft living room that never allowed the speakers develop the sound up to their potential.
When I decided to design and build my audio room I had no restrictions of any kind to deal with, room size or cost restrictions. I was able to look into books that dealt with room acoustics and construction such as, F. Alton Everest's, "Handbook of Acoustics." That book was invaluable in planning what I would build.
The biggest advantage I had was that I was in no hurry to get it done. I began setting the foundation about 43 years ago. The walls were framed 5 years later and the roof went on a short time after that.
My business, producing FRP tooling for the cultured marble and cast polymer industry, took off and for 15 years I didn't have the time to proceed. Then business got bad and while I then had the time to finish it, I didn't have the funds to do so. 7 years ago I sold my business and then had both the time and funds to finish things up.
My good friend and plant manager at my company retired when I sold the company and, like myself, needed something to take up the time. Paul and I worked full time, 40 hours a week, for 5 1/2 years to get the room finished.
Nothing can be better than taking one's time on a big project as it means you can get all sorts of points and ideas from others who travelled the same road.
TW, The center speaker is for the center channel in video as the system is a 7.4 with two ceiling channels for Dolby Atmos.
I always mention to fellow audiophiles that may travel to the area to call should they have time for a listen.
I too bought my Strathearns from him. I also bought about 60 panasonic leaf tweeters from him, the ones I now have in my system. On another note, when I decided to extend the height of the three front speakers, years later, I found them to be unobtbaneium. I looked all over for them for a year and came up empty. It seems as though Mars Distributing, who was the importer of the tweeters, stopped buying them as the minimum order quantity was up to 500 drivers.
Since I was in dire need if them I decided to call Panasonic USA in New Jersey. I finally got to speak with a gal up in the corporations hierarchy. I explained my situation to her and asked if there was anything she could do for me. She said she'd call back and when she did her solution was this. "Mr. Fritz there is no way we can sell you just 36 drivers but I will send that number to you as engineering samples at no charge." I was flabbergasted to say the least as I had paid New York Acoustics $60 each for them.
The lady's name was Jennifer Nitty, a name I'll never forget. I promptly sent her two dozen red roses and a very thankful card.
There are definitely some fine people in this world and she was one of them.
New York Aciustics? That really brings back memories. I bought a lot of drivers from Jim Cox and he was gracious enough to spend many hours on the phone with me as we discussed different options. Among other things I bought Strathearn ribbons from him and several models of Panasonic leaf tweeters. And my mother still uses the 8.2 speaker kit that Jim sold me. I never met the guy but I certainly enjoyed our conversations.
Thank you for describing the evolution of your speaker design. Very interesting indeed.
As things worked out, my experiments with line arrays took a different turn. I ended up with horns for midrange and highs and high-efficiency vintage paper cone woofers. My current setup has the 15” woofers in an open baffle and that has given me the best bass quality that I have had in years.
I first heard a line source system at Stereo Exchange in New York decades ago. It was an Infinity Quantum Line Source and after hearing it I was convinced that line sources would be the design for all future speaker systems I'd build.
I built systems using woofers from Hartley, four 24 inch drivers per side. Eight inch mid bass driver came from from Peerles- P21 rex. Planars from Strathern, Eminent Technology, and Audire. The leaf tweeters always came from Panasonic.
Back then I used a stereo active crossover custom built by New York Acoustics.
Nothing seemed quite right until I heard the Bohlander Graebner drivers designed by Igor Levitsky. After discussing his drivers with him at a CES show I bought 8 of the RD 50 units. At that time Joe D'appolito reviewed a new 7 inch kevlar cone driver from Scan Speak which he wrote up in Speaker Builder magazine. I decided to look into that driver for mid bass.
I had all my driver picked out but needed confirmation that I wasn't making a big mistake in design. I asked for a meeting with both Joe D'Appolito and Vance Dickinson who was a favorite designer for the loudspeaker system industry.
I met both together at a CES and they graciously spent an hour with me over my proposed project. They were both very familiar with all my driver choices and gave me thumbs up on my project. The only problem they mentioned was that I need to have the listening position at least 16 feet from the speakers so that the cylindrical waveforms would integrate properly. My listening position was to be 23 feet so there was no problem there.
After I was half way through in construction I realized that the eight Hartley 24's were not able to put out what was needed below 60 hz.
Since I had purchased a ton, literally, of Krell amplifiers, active crossovers and preamps I called Krell and asked if Dan would be willing to sell me sixteen of the 15 inch metal cone drivers used in their Master Subwoofer Reference. The answer was yes. Dan said he'd call Thilio Stompler at TC Sounds, who built those drivers, and allow me to purchase those drivers. Thilio suggested that since I wanted to use sixteen of that driver he would build them with a surround with an Xmax of 2 inches rather than the 3 1/2 inch Xmax he built for Krell. The thought being that the cone movement would be very little since I was using sixteen drivers and better cone control would be the result of a tighter surround.
Well, everything worked out well using the drivers I chose. Sixteen Krell sub drivers, below 60 hz for all seven speakers in the 7.2 system,Twenty four mid bass drivers up to 200hz, four BG RD50 drivers up to 6,500 hz and 40 Panasonic leaf tweeters per line array column with 30 tweeters facing to the front and 10 to the rear wired out of phase above 6,500 hz. The mid bass, mid range and tweeters were in a horizontal D'Appolito configuration.
Crossovers were Krell KBX three way in mono configuration at 24 db per octave.
The four surround towers were also a three was line source design, I used six Scan Speak 8 inch Revelator kevlar cone drivers from 60 to 500 hz, Six Scan Speak 3 1/2 inch Revelator kevlar cone mid drivers up to 3500 hz and six Scan Speak Revelator dome tweeters from 3.500 hz. on up. Krell KBX active crossovers used for all four 7.5 ft surround towers. The driver configuration was in a mirror configuration fro left to right positions.
The baffles were cast from the polyester/matrix that was chosen for the Theil Audio CS5 loudspeakers. My company did the tooling for the molds used for those baffles and I used the same technology to cast all the baffles for the seven inch mid base drivers in the three front speakers and the four surround towers. The three front towers weigh 1400 lbs. each and the surround towers 540 lbs. each
Everything worked out well after spending 5,400 man hours constructing the seven loudspeakers and I still can't decide if they look better than they sound or vice versa.
Building things has been in my blood for 60 years so this task was not difficult. I built a business supplying polyester and epoxy tooling for the cultured marble and solid surface industry. It required a large pattern shop with every imaginable tool to construct the patterns for bathtubs, shower stalls, vanity told and wall panels etc. This shop was, and is still at my home property which made the project not only easy, but fun.The room and system was a long term goal that I was eager to attempt and complete. All it took was time and the funds to make it all happen.
My choice of gear was easy as I never looked to equipment that was a step down from the best. I realize others would choose different gear and that is what makes competition in any industry great for consumers. I thank you for your posting and comments. Ken
Wow, and Double Wow! That is quite an impressive room and system and obviously the product of much work on your part. Can you share a few more details about the speaker design including your choice of drivers, crossover design etc.?
What a such of work there! Can only admire your dedication building this listening room (actually I would call it auditorium....) from scratch and think the sound performance you can enjoy from your impressive set up. Also like your rig choice, I agree, with Krell stuff you can't be wrong! My compliments.